For example, JP-A-2003-60348 discloses a printed board, which has lands as electrodes connected to an electronic part on a surface of a thermoplastic resin member.
In this printed board, plural one-face conductor pattern films are laminated. Each of the one-face conductor pattern films has a conductor pattern on one face of a resin film formed from a thermoplastic resin. The resin films are bonded to each other by heating this laminating body while pressuring this laminating body by using a hot press machine from above and below. Only the lands (electrode portion) are arranged as a conductor pattern on a substrate surface. The electronic part can be mounted to the lands through solder, etc. without forming a solder resist on the substrate surface except for the lands.
In the mounting of the electronic part, each land is optically recognized on the basis of the difference in intensity of reflected light between the land on the printed board surface and the resin in a circumferential portion of the land, and the electronic part is mounted. Accordingly, it is required that the difference in light reflectivity between the land and the resin of its circumferential portion is large.
However, in the printed board of the above structure, because the difference in intensity of the reflected light between the land and the resin in the circumferential portion of the land is small (contrast is low), the recognition ratio of the land is low.